﻿using System;
using System.Collections.Generic;
using System.Linq;
using Xpedite.Localization;
using Xpedite.Resources.Definitions;

/* Copyright (c) 2010 CBaxter
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 
 * IN THE SOFTWARE. 
 */

namespace Xpedite.Resources
{
  internal interface IResourceContext
  {
    IEnumerable<IResourceDefinition> Definitions { get; }

    IResourceDefinition GetDefinition(String referenceName);
    void CreateResourceDefinition(ResourceType type, String referenceName, IEnumerable<INamedValue<IResourceUrl>> resources);
    void CreateOrExtendResourceDefinition(ResourceType type, String referenceName, IEnumerable<INamedValue<IResourceUrl>> resources);
  }

  internal class ResourceContext : IResourceContext
  {
    private readonly IDictionary<String, Int32> _mutableDefinitions = new Dictionary<String, Int32>();
    private readonly IList<IResourceDefinition> _definitions = new List<IResourceDefinition>();
    private readonly IResourceDefinitionFactory _resourceDefinitionFactory;

    public IEnumerable<IResourceDefinition> Definitions { get { return _definitions; } }

    public ResourceContext(IResourceDefinitionFactory resourceDefinitionFactory)
    {
      Verify.NotNull(resourceDefinitionFactory, "resourceDefinitionFactory");

      _resourceDefinitionFactory = resourceDefinitionFactory;
    }

    public void CreateResourceDefinition(ResourceType type, String referenceName, IEnumerable<INamedValue<IResourceUrl>> resources)
    {
      Verify.NotWhiteSpace(referenceName, "referenceName");
      Verify.NotNullOrEmpty(resources, "resources");

      IResourceDefinition definition = _resourceDefinitionFactory.Create(type, referenceName);

      definition.ReferenceResources(resources);

      _definitions.Add(definition);
    }

    public void CreateOrExtendResourceDefinition(ResourceType type, String referenceName, IEnumerable<INamedValue<IResourceUrl>> resources)
    {
      Verify.NotWhiteSpace(referenceName, "referenceName");
      Verify.NotNullOrEmpty(resources, "resources");

      IResourceDefinition definition;
      Int32 definitionIndex;

      if (_mutableDefinitions.TryGetValue(referenceName, out definitionIndex))
      {
        definition = _definitions[definitionIndex];
      }
      else
      {
        _mutableDefinitions.Add(referenceName, _definitions.Count);
        _definitions.Add(definition = _resourceDefinitionFactory.Create(type, referenceName));
      }

      definition.ReferenceResources(resources);
    }

    public IResourceDefinition GetDefinition(String referenceName)
    {
      IResourceDefinition result;

      result = _definitions.FirstOrDefault(definition => String.CompareOrdinal(definition.ReferenceName, referenceName) == 0);

      if (result == null)
        throw new XpediteException(String.Format(ExceptionMessages.UnknownDefinitionReferenceName, referenceName));

      return result;
    }
  }
}
